What rotten luck. I bought a refrub 27" iMac from apple, because I wanted that apple warranty. Good thing I did. Couldnt afford a new one, and the memory upgrade ability was a MUST HAVE for me. The first day, it started emitting a PAINFULLY loud screatching tone from the speakers. This happen even with the volume all the way down. Seems pretty random. It doesnt crash the machine, it simply nearly makes you deaf its so loud and somewhat high pitched. While its screaching, changing the volume has no effect. Then it just stops. And will do it again a bit later. I was so excited to buy my first Mac ever...... this is a real bummer. I really need this computer RIGHT NOW. Whats the fastest way to get this thing fixed or replaced? Am I going to have to ship it back and wait a full round trip? I have a lot of work to do on it and need it ASAP.